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Improvement Of Season Growth And Resistance To Crown Rust Of Tall Fescue Through Hybridization Between Mediterranean Populations And Adapted Cultivars In Japan, Y Ueyama, S Sato 2025 Kyushu National Agricultural Experiment Station

Improvement Of Season Growth And Resistance To Crown Rust Of Tall Fescue Through Hybridization Between Mediterranean Populations And Adapted Cultivars In Japan, Y Ueyama, S Sato

IGC Proceedings (1977-2023)

Since tall fescue (Festuca arundinacea, Schreb.) is one of the temperate grass species which have good heat tolerance, it is mainly used in grasslands established throughout southwestern Japan where it is hot and humid in summer and mild in winter. The cultivars which have good adaptability to the Japanese condition mainly originated from European or North American populations. Mediterranean populations of tall fescue have good growth potential under the low temperature and short day conditions (Evans et al., 1973) and high levels of crown rust resistance (Wofford et al., 1982). But, the grass species distributed in Mediterranean area are known …


Progress And Prospects For Combining Resistance To Meloidogyne Javanica (Grass Root-Knot Nematode) With Improved Forage Yield In Chloris Gayana (Rhodes Grass), P A. York 2025 Grassland Research Station, Zimbabwe

Progress And Prospects For Combining Resistance To Meloidogyne Javanica (Grass Root-Knot Nematode) With Improved Forage Yield In Chloris Gayana (Rhodes Grass), P A. York

IGC Proceedings (1977-2023)

Meloidogyne javanica, root-knot nematode, has been described as the most serious pest of crops in Central Africa (Daulton & Curtis, 1963). It is widespread in Zimbabwe and very damaging to susceptible crops, particularly tobacco. Good tobacco growers use integrated control measures, sterilizing seed-beds with methyl bromide, lands with ethylene dibromide (EDB) and resting with three or four year Katambora Rhodes grass pastures. Katambora controls M. javanica, improves soil structure, reduces erosion and provides cattle fodder as grazing and poor quality hay. A breeding project has been established in Zimbabwe to combine the better forage production of tetraploid Rhodes grass strains …


Intermediate White Clover - A Model For Clover Persistence On The Gulf Coast In Usa, G W. Evers 2025 Texas Agricultural Experiment Station

Intermediate White Clover - A Model For Clover Persistence On The Gulf Coast In Usa, G W. Evers

IGC Proceedings (1977-2023)

The Gulf Coast region of the USA is classified as subtropical (Rotar and Kretschmer, 1985). Persistence of perennial temper­ate legumes in this area is poor because of climatic, manage­ment, insect and disease factors (Kendall and Stringer, 1985). Frosts during the short-day season limit flowering and seed set of perennial tropical legumes (Rotar and Kretschmer, 1985; Evers, 1973). Annual Trifolium spp. or perennial species which act as annuals, are used in the area (Evers, 1984). The major limitation of annual legumes is dependable reseeding each fall. Although classified as a perennial, Hollowell (1966) has suggested that white clover (Trifolium repens …


Productivity Of Selected High And Low Leaf Area Expansion Festuca Arundinacea Strains, D A. Sleper, C J. Nelson 2025 University of Missouri

Productivity Of Selected High And Low Leaf Area Expansion Festuca Arundinacea Strains, D A. Sleper, C J. Nelson

IGC Proceedings (1977-2023)

A selection program was initiated in 1975 to select for high (H) - and low (L)-LAER in a broad-based population of tall fescue ( Festuca arundinacea Schreb.) to improve vegetative herbage yield (Nelson and Sleper, 1983). Response to divergent selection was linear and symmetric for five cycles (Reeder et al., 1984). Mean increase in selecting for H-LAER was greater than 10 % per cycle ; a mean decrease of more than 8 % per cycle was observed when selecting for L-LAER. Nelson et al. (1977) and Reeder et al. (1984) showed that H­LAER genotypes had wider leaves and higher leaf …


Effects Of Acid Soil Selection On Agronomically Important Traits In Alfalfa, J H. Bouton, D E. Radcliffe 2025 University of Georgia

Effects Of Acid Soil Selection On Agronomically Important Traits In Alfalfa, J H. Bouton, D E. Radcliffe

IGC Proceedings (1977-2023)

Acid soils and their related toxicities are found in every con­tinent of the world. Since liming and fertilization rarely over­come subsoil acidity, poor rooting usually results when grow­ing sensitive legumes such as alfalfa ( Medicago sativa L.). Subsoil liming increased alfalfa yield 46 % over conventionally limed controls indicating deeper rooting achieved through an ability to overcome subsoil toxicity significantly enhanced stand life and productivity (Bouton et al., 1986). If acid soil tol­erance could be incorporated into new multiple-pest resistant cul ti vars without loss of their desirable traits, farmers may real­ize the benefits of any new alfalfa cultivar. The …


Improvement Of Winter, Early Spring Growth In Temperate Pasture Grasses, D R. Kemp, M O. Humphreys, C F. Eagles 2025 Agricultural Research and Veterinary Centre

Improvement Of Winter, Early Spring Growth In Temperate Pasture Grasses, D R. Kemp, M O. Humphreys, C F. Eagles

IGC Proceedings (1977-2023)

Improvement of pasture growth during winter and early spring in temperate regions has been a major goal of many grass breeding programmes. Improvements have been made by selecting for increased yield in early spring, although the basis of these yield improvements is poorly understood. The increase, measured as vegetative components of yield, has been interpreted as improved efficiency of growth at low tempera­tures. However, there is evidence that increased grass growth rates during late winter and early spring are associated with reproductive development (Kemp, 1985, 1988). In this paper we review physiological evidence for growth differences between genotypes during winter …


Kikuyu Grass Improvement For Grazing And Amenity Uses, G J. Piggot, H M. Morgan 2025 MAFTech, NZ

Kikuyu Grass Improvement For Grazing And Amenity Uses, G J. Piggot, H M. Morgan

IGC Proceedings (1977-2023)

Kikuyu grass (Pennisetum clandestinum) is a stoloniferous perennial important in warm-temperate and sub-tropical regions for grazing, erosion control, or amenity uses. Genetic improvement and the registration of cultivars has occurred in Australia (Wilson, 1975; Anon., 1983a, 1983b). Evaluation in New Zealand of this material has investigated the potential for further improvement of kikuyu grass for grazing and amenity uses. In this work, plants considered suitable for selection as a « grazing» type have erectness, large leaves, low stolons number, and high yield. «Amenity» types have fines leaves, thin stolons, low stolon number, and a prostrate and dense habit.


Adaptation Of The Tree Legume Leucaena To Avid Tropical Soils, E M. Hutton 2025 EMBRAPA-CPAC

Adaptation Of The Tree Legume Leucaena To Avid Tropical Soils, E M. Hutton

IGC Proceedings (1977-2023)

Leucaena leucocephala (Lam.) de Wit is native to alkaline soils of Central America, especially Mexico. It is persistent and widely grown in the tropics for leafy, high protein forage giving high productivity in cattle and goats. Leucaena thrives in fert­iles soils with pH's in excess of about 5.5. In the tropics, includ­ing 55 % of South America, 40 % Africa and 37 % Asia, where soils are infertile oxisols and ultisols with pH's 5 or less, com­mon Leucaena varieties like Cunningham lack productivity and persistence. Genetic adaptation of L. leucocephala varieties to acid trop­ical soils was found possible (Hutton, 1981 …


Varietal Differences Of Competitive Ability During Establishment Stage In Dactylis Glomerta And Lolium Perenne, S Sugiyama 2025 Hokkaido University

Varietal Differences Of Competitive Ability During Establishment Stage In Dactylis Glomerta And Lolium Perenne, S Sugiyama

IGC Proceedings (1977-2023)

Herbage grasses are usually grown in association with other herbage species in pastures. But populations which are very productive under the pure swards do not necessarily show high productivity under the mixed swards (Eagles, 1983). Thus, competitive ability becomes important in determining the pro­ductivity of component species in mixed swards. This paper examines the varietal differences of performance during estab­lishment stage when grown in association with other grass species, and morphological characteristics affecting it for two grass species, Dactylis glomerata and Lolium perenne.


Forage And Seed Yield Of 9 Chloris Gayana (Rhodes Grass) Varieties At 3 Sites In Zimbabewe, P A. York, E Nyamandzawo, E Bemont 2025 Grassland Research Stations, Zimbabwe

Forage And Seed Yield Of 9 Chloris Gayana (Rhodes Grass) Varieties At 3 Sites In Zimbabewe, P A. York, E Nyamandzawo, E Bemont

IGC Proceedings (1977-2023)

Katambora Rhodes grass (diploid) is grown in rotation with tobacco in Zimbabwe to control Meloidogyne javanica (root­knot nematode). A 4 year ley is recommended (Martin, 1967) as the nematode can survive in bare fallow for up to 4 years. Katambora produces less herbage than Zimbabwe Giant, and is less palatable than it and other tetraploids. Potential area of use is 200 to 250 thousand ha, and annual replacement 60,000 ha. A breeding project was initiated in 1986 to combine the agronomic value of tetraploid types with the nematode resistance of Katambora. In addition to forage yield and nematode resistance seed …


Bean Yellow Mosaic Virus Resistance In Arrowleaf Clover, G R. Smith, I J. Pemberton 2025 Texas Agricultural Experiment Station

Bean Yellow Mosaic Virus Resistance In Arrowleaf Clover, G R. Smith, I J. Pemberton

IGC Proceedings (1977-2023)

Arrowleaf clover (Trifolium vesiculosum Savi) is a winter annual forage legume often overseeded on warm-season peren­nial grass pastures in the southern region of the United States. Bean yellow mosaic virus (BYMV) can reduce forage pro­duction, seed production and cause plant death of arrowleaf clover (Gibson et al., 1979; Pratt et al., 1982). Resistance to BYMV has been identified in red clover (Trifolium pratense) and the inheritance reported in detail (Taylor et al., 1986). A research program was initiated in 1985 to quantify the effects of BYMV on arrowleaf and to develop BYMV resistant arrowleaf germplasm through recurrent …


Breeding For Resistance To Root Rot In Red Clover, B Andersson, U Kristiansson 2025 Svalof AB

Breeding For Resistance To Root Rot In Red Clover, B Andersson, U Kristiansson

IGC Proceedings (1977-2023)

Red clover (Trifolium pratense L.) is one of the most import­ant species for forage production in Sweden. The use of red clo­ver is however restricted by poor persistence among other things caused by attacks of fungal diseases like clover crown rot and root rot. Investigations have shown (Rufeldt, 1986) that root rot is distributed in almost every field where red clover is grown and is one of the main reasons for the poor persistence. In the same investigations Fusarium roseum, Phoma medicaginis and Cylindrocarpon sp. are pointed out as the most important fungi in the root rot complex. One …


An Induced Non-Nitrogen-Fixing Mutant In Stylosanthes Guianensis, J W. Miles, R Sylvester-Bradley 2025 CIAT

An Induced Non-Nitrogen-Fixing Mutant In Stylosanthes Guianensis, J W. Miles, R Sylvester-Bradley

IGC Proceedings (1977-2023)

A reliable seedling genetic marker would • improve the efficiency of a recurrent selection scheme used in the tropical forage legume Stylosanthes guianensis (Miles, 1985; Cameron and Irwin, 1986). However, seedling markers are rare in S. guianensis. Only presence vs. absence of stem pubescence is reported (Cameron and Irwin, 1986), and this is an unreliable marker in many crosses (Miles, unpublished data). We initiated a project to induce a seedling mutant with gamma radiation. Non-nodulating mutants have been found in other legume species (e.g. Davis et al., 1985) so our project was deliberately designed to identify these if they occurred. …


The Role Of Root System In Tall Fescue (Festuca Arundinacea Schreb.) Productivity, N Gaborcik 2025 Soil Fertility Research Centre

The Role Of Root System In Tall Fescue (Festuca Arundinacea Schreb.) Productivity, N Gaborcik

IGC Proceedings (1977-2023)

Dry matter production of tall fescue (Festuca arundinacea Schreb.) is usually analysed from the following aspects: 1. CO2 metabolism., 2. leaf area index., 3. morphological traits. The relationship between photosynthesis and DM production of this species is relatively complex and not yet clearly elucidated (Wilhelm and Nelson, 1978). On the other hand a close relationship between the leaf area index and DM production of this species was confirmed (Poskuta et al., 1986; Gaborcik, 1986 a). There is relatively less information about the relation­ship between root system characteristics and shoot DM pro­duction (Elkins et al., 1979). The aim of this …


Genetic Variances In Crested Wheatgrass - Alfalfa Mixtures, K H. Asay, D A. Johnson 2025 USDA, Agricultural Research Service

Genetic Variances In Crested Wheatgrass - Alfalfa Mixtures, K H. Asay, D A. Johnson

IGC Proceedings (1977-2023)

Since it was first successfully introduced into North America from Eurasia in 1906 (Dillman 1946), crested wheatgrass [Agropyron cristatum (L.) Gaertner, A. desertorum (Fish. ex Link) Schultes, and A.fragile (Roth) Candargy] has had more impact on revegetation of western rangelands in North America than any other grass. Much of the early crested wheat­grass seedings were made as monocultures ; however, the multiple demands now made on rangelands dictate that other grass, shrub, and forb species be included in the seeding mix. The advantages of grass-legume mixtures in terms of improved forage quality and productivity are well documented (Trenbath, 1974). …


Breeding Acid-Soil Tolerant Lines Of The Tropical Grass Panicum Maximum Jacq., E M. Hutton 2025 EMBRAPA-CPAC

Breeding Acid-Soil Tolerant Lines Of The Tropical Grass Panicum Maximum Jacq., E M. Hutton

IGC Proceedings (1977-2023)

Coloniao (P. maximum) originally from Africa is widely grown in fertile tropical soils, especially of Brazil, because of high yield and feeding value. Its growth and persistence are poor in the extensive acid oxisols and ultisols (pH 4.5-5.0) of South America (68 % in Brazil) where pasture improvement is increasing. The object of the work was to create sufficient variability in the usually apomictic P. maximum by crossing it with some of the few available obligate sexual types of the species (Hanna et al., 1973). This was to give opportunity for selection of acid­soil tolerant lines.


Improvement In Seasonal Production Of Orchardgrass (Dactlyis Glomerata L.) By Selection For Flowering Habit In Autumn Environment, S Sato, F Ikegaya, S Kawabata 2025 Kyushu National Agricultural Experiment Station

Improvement In Seasonal Production Of Orchardgrass (Dactlyis Glomerata L.) By Selection For Flowering Habit In Autumn Environment, S Sato, F Ikegaya, S Kawabata

IGC Proceedings (1977-2023)

Reproductive development of temperate grass species gener­ally proceeds by exposure to low temperature and short daylength and then to moderate temperature and long daylength. However, differentiation and development of inflorescences can be observed even under short day conditions in spring habit types of temperate grasses and grain crops such as ryegrass, wheat, barley and oats. Similar variations called ever-flowering habit were found in orchardgrass. The purpose of this study was to select the materials for ever­flowering habit, to observe their productive behavior under some temperature and photoperiod conditions and to improve seasonal production by using selected materials in orchard­grass.


Breeding White Clover For Resistance To Root Know Nematode, J Van Den Bosch, C F. Mercer 2025 DSIR

Breeding White Clover For Resistance To Root Know Nematode, J Van Den Bosch, C F. Mercer

IGC Proceedings (1977-2023)

White clover (Trifolium repens L.) is the most important legume species used in New Zealand pastoral agriculture (Willi­ams, 1987). However, its growth and fixation of nitrogen can be severely reduced by the root knot nematode, Meloidogyne hapla Chitwood (Widdowson et al., 1973; Yeates et al., 1973; Yeates et al., 1977). This nematode is commonly found throughout New Zealand (Mercer and Woodfield, 1986; Skipp and Christensen, 1983) Chemical control is not economic, or environmentally desir­able. The breeding of resistant cul ti vars may be an effective way to reduce the effects of this pest. Resistance or tolerance in white clover …


Performance Of Trifolium Repens Genotypes Under Grazing In New Zealand Hill Pasture, J.F L. Charlton, D R. Woodfield, J R. Caradus 2025 DSIR

Performance Of Trifolium Repens Genotypes Under Grazing In New Zealand Hill Pasture, J.F L. Charlton, D R. Woodfield, J R. Caradus

IGC Proceedings (1977-2023)

A large area of New Zealand's hill country has been developed into pasture during the past 60 years by removal of scrub vegetation, aerial application of superphosphate fertiliser and aerial oversowing of pasture seeds in mixture. The key legume used was white clover (Trifolium repens L.), either as the cultivar Grasslands Huia, or as uncertified seed. Grasslands Tahora white clover was released in 1984, selected from material collected from moist hill pastures (Williams et al., 1983). Farmers sowing white clover into such pastures now have a choice of using Tahora (specifically bred for moist hill pasture, close-grazed by sheep), …


Breeding For Increased Stolon Branching And Node Density In White Clover, J R. Caradus, A C. Mackay 2025 DSIR, New Zealand

Breeding For Increased Stolon Branching And Node Density In White Clover, J R. Caradus, A C. Mackay

IGC Proceedings (1977-2023)

The stoloniferous habit of white clover (Trifolium repens) is an important factor contributing to its agronomic superiority over other herbage legumes in grazed pastures. High stolon density, which ensures good persistence (Gibson et al., 1963) is most often associated with relatively small leaf size and low harvest index (Caradus & Williams, 1981). Stolon density is a product of proportion of nodes branching and internode length. The aim of the present study was to determine, firstly the heritability of nodal branching and internode length and, secondly the relationship between stolon density and other plant characters.


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